Blends of semi-crystalline materials for inks for direct-to-paper printing

Abstract

Exemplary embodiments provide a phase change ink composition including at least a first semi-crystalline material having a high amorphous content; and at least a second semi-crystalline material having a high crystalline content, such that the phase change ink has a viscosity ranging from about 0.1 cps to about 15 cps at a temperature ranging from about 60° C. to about 145° C. and the phase change ink composition has excellent robustness when forming images or printing on a printing substrate.

What is claimed is: 
     
       1. A phase change ink comprising:
 at least a first semi-crystalline material having a higher amorphous content than a crystalline content therein; and 
 at least a second semi-crystalline material having a higher crystalline content than an amorphous content therein, such that the phase change ink has a viscosity ranging from about 0.1 cps to about 15 cps at a temperature ranging from about 60° C. to about 145° C., wherein the first semi-crystalline material having the higher amorphous content has a T g  value of from about −50° C. to about 100° C. 
 
     
     
       2. The phase change ink of  claim 1 , wherein the phase change ink has a viscosity ranging from about 7 cps to about 15 cps at said temperature. 
     
     
       3. The phase change ink of  claim 1 , wherein the phase change ink has a viscosity ranging from about 10 8  cps or greater at room temperature. 
     
     
       4. The phase change ink of  claim 1 , wherein the phase change ink has a total crystalline content and a total amorphous content in a weight ratio of from about 65:35 to about 95:5. 
     
     
       5. The phase change ink of  claim 1 , wherein the first semi-crystalline material having the higher amorphous content comprises a material selected from the group consisting of gel di-amides, tetra-amides having straight and branched carbon chains, gel tetra-amides, urethanes, and combinations thereof. 
     
     
       6. The phase change ink of  claim 1 , wherein the second semi-crystalline material having the higher crystalline content comprises methyl-amides with straight chain acids. 
     
     
       7. The phase change ink of  claim 1 , wherein the second semi-crystalline material having the higher crystalline content has a viscosity of from about 0.1 to about 10 cps at said temperature. 
     
     
       8. The phase change ink of  claim 1 , wherein the second semi-crystalline material having the higher crystalline content exhibits crystallization (T crys ) and melting (T melt ) peaks according to differential scanning calorimetry (DSC) and the difference between the peaks (T melt −T crys ) is less than about 55° C. 
     
     
       9. The phase change ink of  claim 1 , wherein the second semi-crystalline material having the higher crystalline content has a melting point below said temperature. 
     
     
       10. The phase change ink of  claim 1 , wherein the first semi-crystalline material having the higher amorphous content has a viscosity of from about 10 to about 1000 cps at said temperature. 
     
     
       11. The phase change ink of  claim 1 , wherein the first semi-crystalline material having the higher amorphous content has a viscosity at least 10 8  cps at room temperature. 
     
     
       12. The phase change ink of  claim 1 , wherein the first semi-crystalline material having the higher amorphous content has a molecular weight from about 250 g/mol to about 3000 g/mol. 
     
     
       13. A method of printing, comprising:
 incorporating a phase change ink into an ink jet printing apparatus, wherein the phase change ink comprises at least a first semi-crystalline material having a high amorphous content, and at least a second semi-crystalline material having a high crystalline content, such that the phase change ink has a viscosity ranging from about 0.1 cps to about 15 cps at a temperature ranging from about 60° C. to about 145° C., wherein the first semi-crystalline material having the higher amorphous content has a T g  value of from about −50° C. to about 100° C.; 
 melting the phase change ink inside the ink jet printing apparatus; and 
 causing droplets of the melted ink to be ejected onto a substrate to form an image. 
 
     
     
       14. The method of  claim 13 , wherein the substrate is a final recording sheet and droplets of the melted ink are ejected in an imagewise pattern directly onto the final recording sheet. 
     
     
       15. The method of  claim 13 , wherein the substrate is a coated substrate. 
     
     
       16. The method of  claim 13 , wherein the substrate is an uncoated substrate.